The effect of transport stress on plasma levels of catecholamines, cortisol, corticosteroid-binding globulin, blood cell count, and lymphocyte proliferation in pigs.

The effect of transport stress on the plasma levels of catecholamines, cortisol, and corticosteroid-binding globulin were studied in 6 gilts. To assess the effect on immune status, white blood cells were also counted and the cell-mediated immunity was estimated. The adrenaline level increased significantly during transport, from a basal mean level of 0.03 ng/ml to a plateau level of 0.11 to 0.12 ng/ml. The noradrenaline level fluctuated, but not constantly, during transport. The mean plasma cortisol level before loading was approximately 40 nmol/l and rose immediately after the start of transport to 70 nmol/l (p < 0.05) and to 87 nmol/l (p < 0.01) within 10 and 30 min, respectively. After unloading the cortisol level rapidly decreased and a minimum level was seen 4 h after the transport, whereafter the diurnal rhythm was resumed. The plasma corticosteroid-binding globulin level increased nonsignificantly during the day of transport, from 25 nmol/l to a level of 34 nmol/l, and it continued to increase until a plateau level was reached on the second day after transportation. The total white blood cell number increased significantly (from 13.7 to 15.5 x 10(9) cells/l), the number of lymphocytes decreased significantly (from 8.4 to 7.0 x 10(9) cells/l), and the number of polymorphonuclear neutrophils increased significantly (from 4.3 to 7.2 x 10(9) cells/l) during transport. No significant variation in the proliferation response was seen in the whole blood cell cultures. The main results were the significant signs of simultaneous activity of both the adrenal cortex and the adrenal medulla during transport.